ROLE OF ACTIVE OXYGEN IN UN-INDUCED CATARACT

为了探讨活性氧在紫外线诱发白内障发生机制中的作用，本文研究了紫外线对房水的影响。紫外线对房水中抗坏血酸（AsA）的影响。1) UV-C、UV-B和UV-A对体外房水照射30 min后，HPLC测定的AsA在前者中显著下降，且UV-C照射的AsA下降幅度大于UV-B照射。2) UV-B或UV-A照射10 min后1 d眼水AsA下降，2周后下降幅度更大，且UV-B照射组明显高于UV-A照射组。UV-A和UV-B对眼前段的照射导致房水中AsA的减少，这可能是由于AsA通过血水屏障的主动运输系统受到损伤，导致抗氧化应激防御系统功能障碍所致。阳光对血液水屏障的影响。用激光耀斑细胞仪测定眼睛在室外阳光照射几分钟后，眼内房水蛋白含量明显增加。这意味着暴露在阳光下很容易引起血水屏障的破坏。这些结果表明，UV-A、UV-B和阳光引起房水中生化成分的变化，并可能导致白内障的发生。

In order to study on the role of active oxygen in the mechanism of ultraviolet (UV) induced cataract, the effects of UV on the aqueous humor were examined.1.The effects of UV on ascorbic acid (AsA) in the aqueus humor.1) After the irradiation of UV-C,UV-B and UV-A for 30 min on the aqueous humor in vitro, AsA which was measured by HPLC decreased significantly in the two former and the decrease was greater in the aqueous irradiated with UV-C than in that with UV-B.2) AsA in the aqueous of the eye which received UV-B or UV-A irradiation for 10 min decreased 1 days after the irradiation, and the decrease bacame greater 2 weeks later, much more in the aqueous irradiated with UV-B than in that with UV-A.The irradiation of UV-A as well as UV-B to the anterior segments of the eye cause the decrease of AsA in the aqueous humor which may be due to the damage of active transport system of AsA through the blood aqueous barrier, resulting in the dysfunction of the defensive system against the oxidative stress.2.The effects of sun light on the blood aqueous barrier.After exposure of the eyes to sun light outdoors for several minutes, the protein amount of the aqueous humor of the eye which was measured with laser flare cell meter increased significantly. It means that the disruption of the blood aqueous barrier was easily induced by the exposure to sun light.These results revealed that UV-A as well as UV-B and sun light cause the changes of the biochemical composions in the aqueous humor which may be followed by the cataracgenic conditions.